Cytogenetic abnormalities in de novo acute myeloid leukemia in adults: relation to morphology, age, sex and ethnicity - a single center study from Singapore.

Background: Cytogenetic analysis performed at diagnosis is considered to be the most valuable prognostic factor in acute myeloid leukemia (AML). Large systematic studies of cytogenetic abnormalities in AML patients from Southeast Asia are not available. The karyotypic patterns in AML patients from a single center in Singapore were studied and compared with reports from other regions of the world to identify possible geographic heterogeneity.

Overlapping deletion regions at 11q23 in myelodysplastic syndrome and chronic lymphocytic leukemia, characterized by a novel BAC probe set.

Translocations or deletions involving the 11q23 region have been observed in acute lymphoblastic leukemia (ALL), acute myelocytic leukemia (AML), myelodysplastic syndrome (MDS), and chronic lymphocytic leukemia (CLL). BAC probes encompassing the D11S29 and D11S924 markers and flanking the MLL gene were used in dual color fluorescence in situ hybridization. Fifteen patients with hematologic malignancies and cytogenetic abnormalities of 11q23 were analyzed.

Increased amplification proximal to the MLL gene in acute myeloid leukemia.

Amplification of the chromosomal region 11q23 encompassing the MLL gene has been observed in patients with acute myeloid leukemia (AML). Patients with this abnormality often have a poor response to chemotherapy and short survival. We have studied the regions flanking the MLL gene using 8 bacterial artificial chromosome (BAC) probes and dual color fluorescence in situ hybridization (FISH) analysis.

Detection of HER2/neu gene amplification in archival paraffin-embedded breast cancer tissues by fluorescence in situ hybridization.

We evaluated HER2/neu gene amplification by fluorescence in situ hybridization (FISH) in archival paraffin-embedded breast cancer tissues. Tumors from 63 human invasive breast cancers were categorized into two groups depending on whether the paraffin-embedded tissue blocks had been stored for more or less than 12 months duration. These were subjected to routine and modified FISH protocols.

Effect of fixation period on HER2/neu gene amplification detected by fluorescence in situ hybridization in invasive breast carcinoma.

This study investigated if formalin fixation duration affects HER2/neu gene amplification detection by fluorescence in situ hybridization (FISH) in breast cancer. Tumor tissues from 35 cases were divided into three groups and subjected to two formalin fixation protocols per group (12 hr, 27 hr in the first; 2 hr, 17.5 hr in the second; 28.